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            <div><h4 class="title">
                <a name="asio.reference.io_context.notify_fork"></a><a class="link" href="notify_fork.html"
                                                                       title="io_context::notify_fork">io_context::notify_fork</a>
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    <p>
        <span class="emphasis"><em>Inherited from execution_context.</em></span>
    </p>
    <p>
        <a class="indexterm" name="asio.indexterm.io_context.notify_fork"></a>
        Notify the <a class="link" href="../execution_context.html" title="execution_context"><code
            class="computeroutput"><span class="identifier">execution_context</span></code></a>
        of a fork-related event.
    </p>
    <pre class="programlisting"><span class="keyword">void</span> <span class="identifier">notify_fork</span><span
            class="special">(</span>
    <span class="identifier">fork_event</span> <span class="identifier">event</span><span class="special">);</span>
</pre>
    <p>
        This function is used to inform the <a class="link" href="../execution_context.html"
                                               title="execution_context"><code class="computeroutput"><span
            class="identifier">execution_context</span></code></a> that the process
        is about to fork, or has just forked. This allows the <a class="link" href="../execution_context.html"
                                                                 title="execution_context"><code class="computeroutput"><span
            class="identifier">execution_context</span></code></a>, and the services
        it contains, to perform any necessary housekeeping to ensure correct operation
        following a fork.
    </p>
    <p>
        This function must not be called while any other <a class="link" href="../execution_context.html"
                                                            title="execution_context"><code class="computeroutput"><span
            class="identifier">execution_context</span></code></a> function, or
        any function associated with the execution_context's derived class, is
        being called in another thread. It is, however, safe to call this function
        from within a completion handler, provided no other thread is accessing
        the <a class="link" href="../execution_context.html" title="execution_context"><code
            class="computeroutput"><span class="identifier">execution_context</span></code></a>
        or its derived class.
    </p>
    <h6>
        <a name="asio.reference.io_context.notify_fork.h0"></a>
        <span><a name="asio.reference.io_context.notify_fork.parameters"></a></span><a class="link"
                                                                                       href="notify_fork.html#asio.reference.io_context.notify_fork.parameters">Parameters</a>
    </h6>
    <div class="variablelist">
        <p class="title"><b></b></p>
        <dl>
            <dt><span class="term">event</span></dt>
            <dd><p>
                A fork-related event.
            </p></dd>
        </dl>
    </div>
    <h6>
        <a name="asio.reference.io_context.notify_fork.h1"></a>
        <span><a name="asio.reference.io_context.notify_fork.exceptions"></a></span><a class="link"
                                                                                       href="notify_fork.html#asio.reference.io_context.notify_fork.exceptions">Exceptions</a>
    </h6>
    <div class="variablelist">
        <p class="title"><b></b></p>
        <dl>
            <dt><span class="term">asio::system_error</span></dt>
            <dd><p>
                Thrown on failure. If the notification fails the <a class="link" href="../execution_context.html"
                                                                    title="execution_context"><code
                    class="computeroutput"><span class="identifier">execution_context</span></code></a> object
                should no longer be used and should be destroyed.
            </p></dd>
        </dl>
    </div>
    <h6>
        <a name="asio.reference.io_context.notify_fork.h2"></a>
        <span><a name="asio.reference.io_context.notify_fork.example"></a></span><a class="link"
                                                                                    href="notify_fork.html#asio.reference.io_context.notify_fork.example">Example</a>
    </h6>
    <p>
        The following code illustrates how to incorporate the <code class="computeroutput"><span class="identifier">notify_fork</span><span
            class="special">()</span></code> function:
    </p>
    <pre class="programlisting"><span class="identifier">my_execution_context</span><span class="special">.</span><span
            class="identifier">notify_fork</span><span class="special">(</span><span class="identifier">execution_context</span><span
            class="special">::</span><span class="identifier">fork_prepare</span><span class="special">);</span>
<span class="keyword">if</span> <span class="special">(</span><span class="identifier">fork</span><span class="special">()</span> <span
                class="special">==</span> <span class="number">0</span><span class="special">)</span>
<span class="special">{</span>
  <span class="comment">// This is the child process.</span>
  <span class="identifier">my_execution_context</span><span class="special">.</span><span
                class="identifier">notify_fork</span><span class="special">(</span><span class="identifier">execution_context</span><span
                class="special">::</span><span class="identifier">fork_child</span><span class="special">);</span>
<span class="special">}</span>
<span class="keyword">else</span>
<span class="special">{</span>
  <span class="comment">// This is the parent process.</span>
  <span class="identifier">my_execution_context</span><span class="special">.</span><span
                class="identifier">notify_fork</span><span class="special">(</span><span class="identifier">execution_context</span><span
                class="special">::</span><span class="identifier">fork_parent</span><span class="special">);</span>
<span class="special">}</span>
</pre>
    <h6>
        <a name="asio.reference.io_context.notify_fork.h3"></a>
        <span><a name="asio.reference.io_context.notify_fork.remarks"></a></span><a class="link"
                                                                                    href="notify_fork.html#asio.reference.io_context.notify_fork.remarks">Remarks</a>
    </h6>
    <p>
        For each service object <code class="computeroutput"><span class="identifier">svc</span></code>
        in the <a class="link" href="../execution_context.html" title="execution_context"><code
            class="computeroutput"><span class="identifier">execution_context</span></code></a>
        set, performs <code class="computeroutput"><span class="identifier">svc</span><span class="special">-&gt;</span><span
            class="identifier">notify_fork</span><span class="special">();</span></code>.
        When processing the fork_prepare event, services are visited in reverse
        order of the beginning of service object lifetime. Otherwise, services
        are visited in order of the beginning of service object lifetime.
    </p>
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